(CBS News) WASHINGTON - As Secretary of Defense Leon Panetta offered guarded support Wednesday for Gen. John Allen, new details emerged about correspondence the general had with a Florida woman intertwined in the David Petraeus sex scandal.

"No one should leap to any conclusions here," Panetta said at a news conference in Australia. He added that Gen. Allen, who is still in command of some 68,000 U.S. troops in Afghanistan, "certainly has my continued confidence to lead our forces and to continue the fight."

Allen has been the top U.S. commander in Kabul since July 2011, when he took over for Petraeus, who retired from the Army to head the CIA. Allen had been tapped to be next commander of U.S. European Command and the top NATO general, but his confirmation has been placed on hold due to the investigation.

A senior official has told CBS News correspondent David Martin the vast majority of the emails between Allen and Tampa socialite Jill Kelley were "completely innocuous," and the general believes many of the 20-30,000 pages under scrutiny are duplicates.

The official said that in some of the emails, Kelley would say things like, "saw you on television and you were terrific," and Allen would write back with "thanks, sweetheart." The official said the two never discussed sex and that Allen had never been alone with Kelley.

Nonetheless, CBS News correspondent Bob Orr says Pentagon and FBI sources describe the communications as "potentially inappropriate" and "flirtatious," and another source says they were likely more than just innocent exchanges -- noting that the Pentagon's Inspector General is involved for a reason.

Among the hundreds of emails exchanged between Allen and Kelly - Orr reports that investigators are focusing on one from several months ago. In it, Allen told Kelley he'd just received an anonymous email warning him to stay away from her.

Sources say that the anonymous email came from Broadwell, Petraeus' mistress, who allegedly warned Gen. Allen that Kelley was "a seductress".

Broadwell allegedly sent similar warnings to other military officers at the U.S. Central Command, located near Kelley's Tampa home.

Broadwell, who had been out of sight since the scandal emerged on Friday, was spotted Tuesday night preparing dinner and drinking a glass of wine inside her brother's Washington home.

Kelley was seen inside her Tampa home Tuesday - in plain view of the media circus outside - watching coverage of the scandal on television.

Both Allen and Kelley deny having an affair or any physical relationship.

Still, the emails could potentially cost Allen his career if the Inspector General determines the email exchanges violate the Uniform Code of Military Justice.